Pregnant Mare Weight Gain

Q. We have a 6-year-old Quarter Horse mare and a 21-year-old Paint mare, both in foal to the same Quarter Horse stud. Both were five months along in mid-November (they were bred one week apart). The 6-year-old gained 31 pounds in a six-week period, and the 21-year-old gained 15 pounds in the same time period. Both mares have been ultrasounded and no problems were noted. We have not changed their diets. I was wondering if the weight gain is normal.

via e-mail

A. Differences of weight gain at the levels described are not significant. First, the fetus attains two-thirds of its size in the last third of gestation. Second, the weight of adult horses can easily fluctuate this much just from roughage and water intake. Don't worry about it!

About the Author

A.C. Asbury, DVM

A. C. (Woody) Asbury received his DVM from Michigan State University in 1956, then spent 21 years in California in breeding farm practice and at UC Davis. He joined the faculty at the University of Florida in 1977 and was involved in teaching, research, and administration until 1996. An Emeritus Professor at Florida, he lives in Kentucky, where he and his wife are developing a small farm.

Stay on top of the most recent Horse Health news with FREE weekly newsletters from Learn More